1. Field of the Invention
The present invention relates to a roll holder device for supporting a recording material roll and a supply magazine with the same. More particularly, the present invention relates to a roll holder device and supply magazine in which recording material to be supplied can be appropriately positioned with ease.
2. Description Related to the Prior Art
A printer is used with recording material. For example, a color thermal printer is used with thermosensitive recording paper. The recording material has a form of a recording material roll, which includes a tubular spool shaft and the recording material wound about the tubular spool shaft in a roll form. A roll holder device is used to hold the recording material roll. The combination of the recording material roll and the roll holder device is set in a supply magazine, or directly in a supply chamber of the printer.
The roll holder device includes a pair of paper holder components, each of which is constituted of a holder core and a bearing member. The holder core is inserted in, and fitted inside, an axial end of the tubular spool shaft of the recording material roll. The bearing member supports the holder core in a rotatable manner. The bearing member is fitted in, and secured to, a cutout formed in a holder frame, which is an element included in the supply magazine or the supply chamber of the printer.
To supply the recording material with high precision, it is necessary that the holder core of the paper holder components should be firmly fitted in the tubular spool shaft, and a relative position of the recording material roll relative to the bearing member should be constant as predetermined. If fitting of the holder core on the tubular spool shaft is insufficiently firm, the roll holder device is likely to drop from the tubular spool shaft in setting the recording material roll into the supply magazine or the like. In contrast, if fitting of the holder core on the tubular spool shaft is excessively firm, the roll holder device is highly difficult to unload from the recording material roll.
In setting the recording material roll into the supply magazine, it is likely that turns of the recording material become loose, or the turns at an end face of the recording material roll become shaped conically without a neatly flat shape. To prevent such problems, an adhesive tape is used to secure a front edge of the recording material to the outside of the recording material roll. It is necessary to remove the adhesive tape after the recording material roll is set into the supply magazine. However, an inadvertent user is likely to forget the removal upon setting the recording material roll. If the printer is operated for supply of the recording material with the adhesive tape kept attached, no recording material is supplied. Furthermore, a mechanism for paper supply is likely to be broken in the printer or the supply magazine.
The roll holder device according to the prior art includes the paper holder components having an equal size. If the paper holder components are set on the end faces of the recording material roll in either orientation, the roll holder device can be set in the supply chamber or the supply magazine. A problem arises in failure in supply of the recording material because of a situation where the recording material roll is set in the supply magazine in a direction opposite to a proper direction.
Another problems lies in that propriety in a fitted state of the paper holder components into the tubular spool shaft cannot be checked readily. The paper holder components are likely to be set in a halfway inserted state at the supply magazine or the printer. It is conceivable that a plate spring is used in the supply magazine or the supply chamber of the printer for pressing an end face of the paper holder components to position the same in the axial direction. If the recording material roll is set with the paper holder components oriented improperly, the plate spring is deformed. There occurs an offset state of the recording material roll in the width direction.
Furthermore, a pad with a felt member is provided in the roll holder device, and pressed against the holder core for application of rotational load. This is for the purpose of applying back tension to the recording material, and preventing oblique movement or jamming of the recording material by increasing reliability in the feeding. However, the pad causes application of rotational load also in the course of winding the recording material back to the recording material roll. In the course or rewinding, there occurs a problem of looseness between turns of the recording material in the recording material roll because a considerable difference occurs in an angular speed between the inner turns and the outermost turn.
In view of the foregoing problems, an object of the present invention is to provide a roll holder device and a supply magazine in which precision in supply of recording material can be high by firmly keeping paper holder components positioned on a tubular spool shaft of a recording material roll.
Another object of the present invention is to provide a roll holder device and a supply magazine in which end faces of a recording material roll can be neatened to prevent loosening of the recording material roll to be set into a supply chamber.
Still another object of the present invention is to provide a roll holder device and a supply magazine in which setting of a recording material roll is allowed only which the recording material roll is oriented in an appropriate direction.
Another object of the present invention is to provide a roll holder device and a supply magazine in which oblique movement or jamming of recording material can be prevented by lowering rotational load applied to a holder core while the recording material is wound back.
In order to achieve the above and other objects and advantages of this invention, a roll holder device is for use with a recording material roll including a tubular spool shaft and continuous recording material wound about the tubular spool shaft in a roll form. In the roll holder device, first and second holder cores are inserted in respectively first and second ends of the tubular spool shaft. In a supply magazine, there is a holder frame member which supports the first and second holder cores in a rotatable manner. In the roll holder device, an anti-dropping mechanism prevents the tubular spool shaft from dropping from the first and second holder cores by pushing a shaft inner surface of the tubular spool shaft.
Furthermore, a bias mechanism biases and presses the anti-dropping mechanism against the shaft inner surface.
The anti-dropping mechanism includes a push surface for contacting the shaft inner surface. Plural claws are formed to project from the push surface, for being thrust into the shaft inner surface.
The first holder core has a greater size in an axial direction than the second holder core.
Ends of the first and second holder cores are engaged with each other.
Furthermore, a core sleeve is formed with the first holder core. An access opening is formed through the core sleeve. The anti-dropping mechanism includes an anti-dropping lever, shiftable between first and second positions, contained in the core sleeve when in the first position, and protruded toward an outside of the core sleeve through the access opening when in the second position, for pressing the push surface against the shaft inner surface.
The anti-dropping lever has a driven end portion disposed in the core sleeve. Furthermore, a connection shaft is formed with the second holder core, inserted in the core sleeve, for shifting the anti-dropping lever from the first position to the second position by pushing the driven end portion.
The first and second holder cores are rotatable in unwinding and winding directions. Furthermore, a load changer mechanism applies higher rotational load to the first and second holder cores during rotation in the unwinding direction than during rotation in the winding direction.
According to one aspect of the invention, the load changer mechanism includes a friction pad member for effecting braking operation to each of the first and second holder cores. A one-way clutch connects each holder core to the friction pad member during rotation in the unwinding direction, and disconnects each holder core from the friction pad member during rotation in the winding direction.
The one-way clutch includes a ratchet wheel, secured to each holder core, and having at least one ratchet claw. A tube member is engaged with the friction pad member, for containing the ratchet wheel, wherein the tube member has at least one tooth disposed inside, and when each holder core rotates in the unwinding direction, rotates in the unwinding direction by mesh of the tooth with the ratchet claw, and when each holder core rotates in the winding direction, disengages the tooth from the ratchet claw.
Furthermore, first and second cutouts are formed in the holder frame member, for supporting respectively the first and second holder cores in a rotatable manner. At least one orientation regulator mechanism prevents the first holder core from being set in the second cutout or the second holder core from being set in the first cutout.
According to another aspect of the invention, furthermore, first and second bearing members are inserted in respectively the first and second cutouts, for supporting the first and second holder cores in a rotatable manner, to constitute the at least one orientation regulator mechanism.
The first and second cutouts have respectively a pair of edges extending with an inclination relative to an inserting direction of the recording material roll. The at least one orientation regulator mechanism includes an inclined surface, formed on the first and second bearing members, inclined according to the pair of the edges, for blocking erroneous insertion of the first bearing member into the second cutout and of the second bearing member into the first cutout.
Furthermore, first and second handle members are secured to the first and second bearing members in a pivotally movable manner, set substantially erect to the first and second bearing members upon being moved up, for pushing end faces of the recording material roll, to prevent looseness of the recording material roll.
According to still another aspect of the invention, furthermore, a roll regulator mechanism pushes a pair of end faces of the recording material roll with the first and second holder cores secured thereto, to prevent looseness of the recording material roll. An unblocking mechanism releases the recording material roll from pressure of the roll regulator mechanism in response to setting of the recording material roll in the holder frame member.
Furthermore, a bias mechanism biases the roll regulator mechanism toward the end faces of the recording material roll. The unblocking mechanism moves the roll regulator mechanism away from the end faces of the recording material roll against the bias mechanism upon being set in the holder frame member.
The roll regulator mechanism includes first and second handle members, set at the first and second ends of the tubular spool shaft in a pivotally movable manner, shifted substantially erect to the first and second bearing members upon being moved up, for pushing end faces of the recording material roll.
Furthermore, first and second bearing members are secured to the holder frame member, for supporting the first and second holder cores in a rotatable manner. The first and second handle members are secured to the first and second bearing members in a pivotally movable manner, and the bias mechanism biases each of the first and second bearing members toward the recording material roll.
Furthermore, a cutout is formed through the holder frame member, has one end open at an edge of the holder frame member, for supporting each bearing member in a rotatable manner. The unblocking mechanism includes an inclined edge portion, formed at the open end of the cutout, inclined toward an inside of the holder frame member, for guiding insertion of each bearing member into the cutout. A great-diameter portion is formed at an axial end of each bearing member with a greater diameter, pushed by an edge of the cutout by insertion of each bearing members into the cutout, for sliding each bearing member away from the recording material roll.
The roll holder device is loadable in a supply magazine for a printer, and the holder frame member is disposed in the supply magazine.
According to another aspect of the invention, a supply magazine is for use with a recording material roll including a tubular spool shaft and continuous recording material wound about the tubular spool shaft in a roll form. In the supply magazine, first and second holder cores are inserted in respectively first and second ends of the tubular spool shaft. A spring plate member pushes an axial end of the first or second holder core, to position the recording material roll in an axial direction. A regulator member is disposed behind the spring plate member, for regulating a shift of the spring plate member being pushed.
Furthermore, a magazine body contains the recording material roll. A holder frame member supports the first and second holder cores in the magazine body in a rotatable member. The spring plate member and the regulator member are secured to an inner face of the magazine body.